《淮南子》由〈要略〉定位作一具外王性格的典籍，被寄付以經紀天下的政用性；所論治道確多有可觀。然則〈地形〉作為《淮南》探究地理（「下揆之地」）的一重要篇章，內容則以幻設地理為主體，這顯然並不符合當今對地理學之實用價值的理解，也與同一時期司馬遷對地理學的認知有別。本文故考察周秦漢向政用而提供可利用性之地理學的普遍開展情況，以實際估定〈地形〉於漢世的可能定位，並最終指出該系地理學的政用性曾於傳說時期實現，並也發生於東漢之世，但於西漢則大抵處於隱沒狀態之中。

Huainanzi is characterized as a work of the outer kingliness in one of its chapters, “Yaolue” (“An overview of the essentials”) for political purposes in governing and benefitting the people. However, “Dixing” (“Topography”) as an important chapter of Huainanzi that explores the geography (of "Xiakui land") is based on fictionalized geography. This obviously does not conform to the current understanding of the practical value of geography, different from Sima Qian’s view of geography during the same period. Therefore, this article examines the general development of geography that provides availability for political use in the Zhou, Qin and Han dynasties, in order to infer to the possible positioning of “Dixing” in the Han dynasty. The author points out that the political use of this geography system had been realized in the Legendary Era and occurred in the Eastern Han dynasty, but generally was in decline in the Western Han dynasty.